<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2009 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
// $Id: Page.class.php 75 2011-03-29 16:58:45Z nicholasinlove1986@gmail.com $

// +----------------------------------------------------------------------
// | @author nicholas <nicholasinlove@126.com>
// +----------------------------------------------------------------------
// | @link ( http://www.yurnero.net )
// +----------------------------------------------------------------------
// | 自动适应范围的页码分页 $rollPage为显示的页码数
// +----------------------------------------------------------------------
// | 可以利用&nbsp;改变间隙 可以显示$upPage,$downPage或屏蔽
// +----------------------------------------------------------------------

class Page extends Think {
    // 起始行数
    public $firstRow	;
    // 列表每页显示行数
    public $listRows	;
    // 页数跳转时要带的参数
    public $parameter  ;
    // 分页总页面数
    protected $totalPages  ;
    // 总行数
    protected $totalRows  ;
    // 当前页数
    protected $nowPage    ;
    // 分页的栏的总页数
    protected $coolPages   ;
    // 分页栏每页显示的页数
    protected $rollPage   ;
	// 分页显示定制
    protected $config  =    array('header'=>'records','prev'=>'&laquo; Previous','next'=>'Next &raquo;','first'=>'1...','last'=>'最后一页','theme'=>'Total %totalRow% %header%, Pages: %nowPage%/%totalPage%, %first% %upPage% %linkPage% %downPage% %end% %input%'); //屏蔽 %select%  %prePage% 上$rollPage页 %nextPage% 下$rollPage页 下拉框

    /**
     +----------------------------------------------------------
     * 架构函数
     +----------------------------------------------------------
     * @access public
     +----------------------------------------------------------
     * @param array $totalRows  总的记录数
     * @param array $listRows  每页显示记录数
     * @param array $parameter  分页跳转的参数
     +----------------------------------------------------------
     */
    public function __construct($totalRows,$listRows,$parameter='') {
        $this->totalRows = $totalRows;
        $this->parameter = $parameter;
        $this->rollPage = C('PAGE_ROLLPAGE');
        $this->listRows = !empty($listRows)?$listRows:C('PAGE_LISTROWS');
        $this->totalPages = ceil($this->totalRows/$this->listRows);     //总页数
        $this->coolPages  = ceil($this->totalPages/$this->rollPage);
        $this->nowPage  = !empty($_GET[C('VAR_PAGE')])?$_GET[C('VAR_PAGE')]:1;
        if(!empty($this->totalPages) && $this->nowPage>$this->totalPages) {
            $this->nowPage = $this->totalPages;
        }
        $this->firstRow = $this->listRows*($this->nowPage-1);
    }

    public function setConfig($name,$value) {
        if(isset($this->config[$name])) {
            $this->config[$name]    =   $value;
        }
    }

    /**
     +----------------------------------------------------------
     * 分页显示输出
     +----------------------------------------------------------
     * @access public
     +----------------------------------------------------------
     */
    public function show() {
        if(0 == $this->totalRows) return '';
        $p = C('VAR_PAGE');
        $nowCoolPage      = ceil($this->nowPage/$this->rollPage);
        $url  =  $_SERVER['REQUEST_URI'].(strpos($_SERVER['REQUEST_URI'],'?')?'':"?").$this->parameter;
        $parse = parse_url($url);
        if(isset($parse['query'])) {
            parse_str($parse['query'],$params);
            unset($params[$p]);
            $url   =  $parse['path'].'?'.http_build_query($params);
        }
        //上下翻页字符串
        $upRow   = $this->nowPage-1;
        $downRow = $this->nowPage+1;
        if ($upRow>0){
            $upPage="<a href='".$url."&".$p."=$upRow' class='prev page-numbers'>".$this->config['prev']."</a>\n";
        }else{
            $upPage="";
			//$upPage="<span class='disabled'>".$this->config['prev']."</span>\n";
        }

        if ($downRow <= $this->totalPages){
            $downPage="<a href='".$url."&".$p."=$downRow' class='next page-numbers'>".$this->config['next']."</a>\n";
        }else{
            $downPage="";
			//$downPage="<span class='disabled'>".$this->config['next']."</span>";
        }
        // << < > >>
        if($nowCoolPage == 1){
            $theFirst = "";
            $prePage = "";
        }else{
            $preRow =  $this->nowPage-$this->rollPage;
            $prePage = "<a href='".$url."&".$p."=$preRow' >上".$this->rollPage."页</a>";
        }
		//偏移3页
        if($this->nowPage - 3 > 0){
				  $theFirst = "<a href='".$url."&".$p."=1' class='page-numbers'>".$this->config['first']."</a>\n";
        }
        if($nowCoolPage == $this->coolPages){
            $nextPage = "";
            $theEnd="";
        }else{
            $nextRow = $this->nowPage+$this->rollPage;
            $theEndRow = $this->totalPages;
            $nextPage = "<a href='".$url."&".$p."=$nextRow' >下".$this->rollPage."页</a>";
            $theEnd = "<a href='".$url."&".$p."=$theEndRow' class='page-numbers'>...".$theEndRow."</a>";
        }
        // 1 2 3 4 5
        $linkPage = "";
		
		//页码范围计算
		$init = 1;//起始页码数
		$max = $this->totalPages;//结束页码数
		$pageoffset = ($this->rollPage-1)/2;//页码个数左右偏移量
		
		//分页数大于页码个数时可以偏移
		if($this->totalPages>$this->rollPage){
			//如果当前页小于等于左偏移
			if($this->nowPage<=$pageoffset){
				$init=1;
				$max = $this->rollPage;
			}else{//如果当前页大于左偏移
			//如果当前页码右偏移超出最大分页数
				if($this->nowPage+$pageoffset>=$this->totalPages+1){
					$init = $this->totalPages-$this->rollPage+1;
				}else{
				//左右偏移都存在时的计算
					$init = $this->nowPage-$pageoffset;
					$max = $this->nowPage+$pageoffset;
				}
			}
		}
		//echo $init.';'.$max;
        for($i=$init;$i<=$max;$i++){
            $page=$this->nowPage;
			if($i==$page){
				$linkPage .= "<span class='page-numbers current'>".$page."</span>\n";
			} else {
				$linkPage .= "<a href='".$url."&".$p."=$i' class='page-numbers'>".$i."</a>\n";
			}
        }  
		/*输入框*/     
        $input = 'Go <input style="width:20px; padding:0;font:10px Verdana;background:#aaa;" onkeypress="var keyChar=event.keyCode;if(keyChar == 13){location.href=\''.$url.'&'.$p.'=\'+this.value}" />';
		/*下拉框*/
		$select.='Go&nbsp;&nbsp;<select name="topage" size="1" onchange="window.location.href=\''.$url.'&'.$p.'=\'+this.value">\n';
		for($i=1;$i<=$this->totalPages;$i++){
			if($i==$page) $select.="<option value='".$url."&".$p."=$i' selected>".$i."</option>\n";
			else $select.="<option value='".$url."&".$p."=$i'>".$i."</option>\n";
		}
		$select.="</select>";
        
        $pageStr     =     str_replace(
            array('%header%','%nowPage%','%totalRow%','%totalPage%','%upPage%','%downPage%','%first%','%prePage%','%linkPage%','%nextPage%','%end%','%input%','%select%'),
            array($this->config['header'],$this->nowPage,$this->totalRows,$this->totalPages,$upPage,$downPage,$theFirst,$prePage,$linkPage,$nextPage,$theEnd,$input,$select),$this->config['theme']);
        return $pageStr;
    }
}

?>